The shuttles of Infinity Unlimited jump between parallel Earths, seeking adventure, profit, knowledge, and even entertainment. But a parallel called Centrum has also developed the technology to hop between the worlds . . . and they want to rule them all. The Infinity Patrol must deal with their ruthless rivals, as well as with world-jumping criminals, and with the possibility that the secret of dimension travel might escape to some of the really nasty alternate worlds like Reich-5.

Welcome to the core setting of GURPS Fourth Edition! Every other GURPS setting is on one of the Infinite Worlds timelines . . . whether they know it or not! GMs can use this to create a whole meta-campaign, or just as an excuse to move characters between worlds when the plot requires it.